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diy solar

Smallest Mini-Split?

33.1 is the highest SEER.
Wow that’s high. At that level you’re probably wasting energy by NOT running the A/C!

My pioneer 9000btu ~22 seer is still running great after 2 years; I think that’s still considered “high seer” as the cheapest ones are 16-18ish.

they’re a real pain to install though.
 
On a similar note, folks who camp in the sun use Aluminet (reflective netting) to greatly reduce heat in tents, RV's and under canopies. I have a 14' x 40' piece that i drape over my Sprinter Winnebago and it makes all the difference in the world for my solar swamp cooler to be effective.

Just don't expect it to last very long in any appreciable wind. Those things are NOT built to last.
 
Is anyone aware of a small mini-split?

Say 5,000 BTU?

I have a 20 foot off grid shipping container that I spend some time in on occasion. It is located in Arizona so there is a surplus of solar energy and some brutal temperature swings.

I basically just want to take the edge off a freezing morning or a 100 degree fahrenheit afternoon.

It won't be insulated, by choice, so there are no high hopes for great climate control. I'm happy to waste some solar power production just to take the edge off.

Another plus of a mini-split system for my application is one relatively small hole to cut into the steel. I won't consider a cheap window unit for that reason.

Edit: removed the word cheap
Does your container have a window? How about a small portable swamp cooler that you put the vent in the window opening, then you can remove it when done. You can blow it directly on you. W/O insulation, the container will be like an oven. I have a 24k mini split. It is not the greatest thing in the world for heat when really cold. It helped fairly well when over 100 degrees in an old house with new insulation in 2x4 walls and new windows. Otherwise, it would not be nice at all. You will probably have to run it on Turbo and have a fan blowing on you. Although they do say to have all doors and windows closed so it sounds like an evaporative cooler might be best for you, since the door is open just smaller than coyote head size.
 
Need the heat on cold mornings
My opinion? Get the minisplit, paint white. And insulate.

Cold doesn’t ‘gain’ like heat from the sun will. The BTUs needed to heat in the AM will be far more attainable than the energy required to cool a container that’s wants to hit 160*F at 1pm. One window on the east side will provide both a means of not getting locked in and a fresh air source if desired. Never mind light deprivation issues.
I really don’t think 6000btu is going to cut it for you.
 
No insulation… by choice? That makes zero sense if this structure is to be occupied.
A shipping container in most areas of Arizona is basically a big solar slow cooker / oven. Perhaps you’ve been in the heat too long?
Insulating should be #1, maybe a tie with painting the container the whitest white available.
both are relatively inexpensive, easily done, and are the most bang for the ?.
Then evap cooler or ac. And a small east facing window or 2, and a few fans.
 
I've spent quite a bit of time down south in the past 40 years and understand why the OP says "NO WINDOW".
Something about a window in a shipping container in the AZ desert sounds wrong.
 

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I’m talking about small horizontal windows, like 1’x2‘, fitted up near the ceiling. you could always attach a wire grate on the inside, or weld it to the outside if security is an issue. Or plant cactus, or other indigenous gnar gnar plants in front of it. Or razor wire. Windows being something for ventilation when it’s not blazing hot out, not to mention having some natural light.

And, looking at your graphic… if you’re implying immigrants trudging through the desert from Mexico will break in and steal whatever they can, well that’s certainly possible if you’re on a route, and if they are carrying tools (assuming the place has been made relatively secure).
But they are traveling light, trying to survive the trip, get to their destination, and aren‘t usually going to be interested in carrying a heavier load, unless it’s water, food, or shelter.
 
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wire grate on the inside, or weld it to the outside if security is an issue
From some of my construction experience and fabrication of various things for security (including a “level 5” facility), I’m pretty sure it would be far easier to defeat the lock in the door recess and break into the container door than it would be defeat a secured window if breaking in was attempted. Either way an acetylene torch or grinder and a bit of time would be involved. Drawing attention to oneself with sparks and flame in the night is probably not a thief’s modus operandi. Everything’s possible I suppose….

But as far as cooling a container in the desert- a non-absorbing coating (white paint) is defense one on heat gain.

Venting heat high up with cooling input could be effective. But leaving the door open would essentially let all the cooled air flow out the bottom and the environment flow into the top.

However, closing the door and venting high would essentially begin to ’fill’ the container with cooled air: initially. After a short time close the high vent and let the AC work.
I’m just not convinced that’s the uninsulated volume of a steel container can be effectively cooled with 3000btu.
 
I’m just not convinced that’s the uninsulated volume of a steel container can be effectively cooled with 3000btu.

Absolutely not and that was never the goal. As stated in posts #1 and #3 my goal was to simply “take the edge off” in “my personal square footage”.

I’ve accomplished that with a fan and spritzing some water on hot days and a Mr. Buddy propane tank heater on cold mornings.

I’m only there for relatively short periods, probably less than 100 hours a year for some ham radio contests and other nonsense.

I have no problem if people explore other goals here but my situation is sorted to my satisfaction.
 
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It would be nice to find a soft start stand alone unit. Double hose that could vent through the floor. This would address many conex issues.
 
Your idea of a portable A/C and space heater sounds like the easiest way to go.
I get the idea of just taking the edge off by sitting in the "breeze" of either.
I used a portable much the same way. It wouldn't cool the room but provided much needed relief.
might want to use insulated flexible duct pipe for the A/C discharge on a long run

My wife has a infrared heater similar to this to sit outside. It keeps her warm and toasty but you may not have enough headroom to install it
https://www.amazon.com/Electric-Col...f/dp/B08P47M9XF/ref=psdc_553782_t2_B0755QDMKD
 
Your biggest issue with regards to heat gain and loss will be radiation.


Actually my most uncomfortable time is when I operate a 160m contest overnight in January. I am very cold by sunup.

Mr. Buddy helps a lot but I love when the sun comes up and the container starts creaking and popping as the suns radiation starts to help out.

I shouldn’t admit this in public but I actually cuddle up to the metal side in the sun at that point in the morning and don’t want to lose that. ?
 
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I recently installed a mini split in our master bedroom. Since it is just the two of us, we run it at nighttime instead of cooling the whole house. It is a 900 btu, cools and heats. You can buy them pretty well everyhere in Texas for 350 to 500. You do the install. We run it off of battery backup off our solar setup. When you turn it on, it goes to 12 amps but then backs off to about 4 amps. Going to do the same for my recent patio enclosure.
 
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Actually my most uncomfortable time is when I operate a 160m contest overnight in January. I am very cold by sunup.

Mr. Buddy helps a lot but I love when the sun comes up and the container starts creaking and popping as the suns radiation starts to help out.

I shouldn’t admit this in public but I actually cuddle up to the metal side in the sun at that point in the morning and don’t want to lose that. ?
You were right… you shouldn’t have admitted that, or disclose is probably the more accurate term.
T M I
#cringy
 
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